Since the development of electronic digital computers, efficient removal of heat has played a key role in insuring the reliable operation of successive generations of computers. In many instances the trend toward higher circuit packaging density to provide reductions in circuit delay time (i.e., increased speed) has been accompanied by increased power dissipation requirements.
One approach to cooling such electronic components was to utilize hybrid air-to-water cooling in otherwise air-cooled machines to control cooling air temperatures. With the precipitous rise in both chip and module powers that occurred throughout the 1980s, it was determined that the most effective way to manage chip temperatures in multichip modules was through the use of indirect water-cooling.
The increased use of complementary metal oxide semiconductor (CMOS) based circuit technology in the early 1990s led to a significant reduction in power dissipation and a return to totally air-cooled machines. However, this was but a brief respite as power and packaging density rapidly increased, first matching and then exceeding the performance of the earlier machines. These increases in packaging density and power levels have resulted in unprecedented cooling demands at the package, system and data center levels, leading to a return of water cooling.
Many large scale computing systems contain multiple dual core processor modules, often as many as 16 or more. An assembly of an equal number of cold plates is often used to cool the processors. The assembly in one prior system consists of the cold plates (one cold plate for each processor module), tubing that connects groups of cold plates in series, tubing that connects each grouping of cold plates, or quadrant, to a common set of supply and return lines, and two hoses that connect to system level manifolds in the rack housing the processor modules or nodes.
The ability to remove a node from the liquid cooling system without adversely affecting the operation of the remaining system is provided by fluid couplers that can be uncoupled quickly and easily with virtually no liquid leakage (i.e. “quick connects”).
However, due to the ever increasing demand for computing capacity and often limited available space, more processor nodes are placed in closer proximity to one another with less and less available free space for the cooling systems. As such, known quick connect fittings used in prior cooling systems often do not fit in the allocated space. Other than known quick connect fittings, other options use a nut to seal either an O-ring, or a compression ring that pinches the tubing to make a seal. These connectors are often not feasible due to the extreme size of the components and the fact that there is no available tool or wrench clearance to connect and disconnect these types of fitting. Additionally, tightening these types of fittings produces a high torque on the delicate brazed tube assembly connected to the cold plates. The twisting torque could damage tubing, or put stress on electronic modules that the cold plates interface with.
Therefore, an improved fitting assembly that overcomes these problems in the prior art while still offering durable and reliable connect and disconnect operations in a minimum of available space is needed.